Timing mechanism



R. E. MCCLURE TIMING MECHANISM March l2, 1940.

Filed Oct. 30. 1937 2 Sheets-.Sheet l aww wlw Patented Mar. 12, 1940UNITED STATES PATENT OFFiCE TIMING MECHANIsM Application October 30,1937, Serial No. 171,872

3 Claims.

Tlrr's invention relates to an apparatus for successively closing aplurality of electric control circuits at preselected times. Devices ofthis charactejr have numerous applications in industry. The one forwhich the invention has been specially designed and in connection withwhich it will be described herebeloW is that of controlling a radioreceiver provided with automatic tuning equipment. The invention is,however', not limited to this application, but may be employed for anyother service where it is desired successively to close a plurality ofcontrol circuits.

Automatic tuning has now become accepted in the radio receiver eld, andalthough a nurnber of different types of mechanisms have been developed,a requirement common to many is that a circuit identified With aparticular broadcasting station be energized when it is desired toreceive broadcasts from that station. The mechanism foi` actuallyturning the tuning shaft of a receiver provided with rotary tuningcondensers forms no part of my present invention, although a mechanismof this type is disclosed in my Patent No. 2,650,739, granted August ll,1936.

The present invention as applied to radio receivers having tuning shaftsconcerns only a mechanism for closing contacts at preselected times forenergizing the circuits necessary to cause the conventional automatictuning mechanism to operate to tune the receiver to the deired station.

A clear understanding of the invention may be obtained from aconsideration of the following detailed description, which refers to theaccompanying drawings illustrating a present preferred embodiment. Inthe drawings:

Figure l is a transverse sectional view through a device for controllinga conventional automatic tuning mechanism for a receiver having a rotarytuning shaft;

Figure 2 is a sectional View taken along the line II-II of Figure l; theline I-I of Figure 2 indicates the plane on which the section of Figurel is taken;

Figures 3, 4, and are perspective views of structural details; and

Figure 6 is a circuit diagram with reference to which the operation ofthe mechanism shown in Figures l through 5 will be described.

Referring now in detail to the drawings and for the present to Figures 1through 5, the apparatus there shown is contained Within a case I0,comprising a base Il, front and rear Walls I2 and I3, a top I4, and asloping wall I5, together (Cl. ZIM-37) with suitable end walls, notshown. A plurality of bearing standards i5 are disposed in alignment andin spaced relation along the length of the base l i. The standards havefeet il, whereby they may be secured to the base II, as by bolts i8.Each standard has a bifurcated upper end I9.

Cooperating with each of the standards l5 is a bushing Each bushing 2thas a pair of peripheral ribs 2l extending therearound and defining agroove 22 therebetween. Grooves 23 are formed adjacent opposite ends ofthe bushing and are adapted to receive crescent-shaped lock Washers2:1-,` As shown in Figure 2, the bifurcated end of each standard I6 isadapted to receive a bushing Zu and to enter the peripheral groove 22 4thereof.

Manually adjustable timing disks 25 are journaled on the bushings 29 onopposite sides of their supporting standards It and are held in piace bylock washers 2li. Each disk has a time scale 26 around its periphery andthe edge of each disk extends through a slot 2 in the sloping wall iti,as shown in Figure l. Each disk may be individually adjusted manually bymeans of the peripheral portion thereof extending through the slot 2l,Each disk 25 has a contact ring 23 on one face thereof. Each ring 2&3has a projection 29 extending therefrom. Relatively fixed contactfingers @il are mounted on the base ii and have sliding Contact with therings .2s of the disks 25. The fingers 30 are yieldable and may bedisengaged from their rings shown in dotted lines in Figure 2, by camshafts 3i, journaled in the front Wall I2 and suitable bearings 3i andoperable by knobs 33, se-

cured to the ends of the shafts extending through anism of aconventional radio receiver, i. e., one

with a rotary tuning shaft. As already stated, one example of suchautomatic tuning mechanism shown in my prior Patent No. 2,050,719.

A clock i is mounted in the. case ifi on a pedestal St, or othersuitable support, carried on the base Il. The clock is preferably atwenty-four hour clock, that is, one in which the main shaft makes acomplete revolution in twentyfour hours. The main shaft of the clock hasa rearward extension 37, extending axially through the bores of thebushings 20. The outer end of the extension 3'I may be journaled in asuitable type of bearing, not shown. Contact arms 38 are secured to theshaft 37 and turn therewith.

Each of the arms 38 has sliding engagement with the face of one of thedisks 25 which is provided with the contact ring 28. The arms 38 are ofsuch length that they will engage the projections 29 of the rings 28when aligned therewith, but will not engage the rings 28. The arms 38are all disposed in the same radial plane relative to the shaft 3l. Theshaft 31 is connected to a suitable source of electric current by anyconvenient means, not shown. By this arrangement, rotation of the shaft31 will cause the connections 34 to be energized at preselected times,depending upon the adjustment of the disk 25. This will be made clear inthe following description of operation, referring more particularly toFigure 6.

In Figure 6, a radio receiver having an automatic tuning device adaptedto turn the tuning shaft of the receiver to appropriate positions whenproperly energized is indicated at 39. The

- connections 34 are brought out from the receiver in the form of acable. An electromagnetic switch 4G is provided for automaticallyconnecting the receiver 39 to its current source at a preselected time.A manual switch 4l is also connected in the circuit. The switch 4l! hason and olic coils connected to two of the disks 25 indicated in Figure 5at 25a and 25h, respectively. A transformer 42, which is connectedacross the supply by closure of the switch 4I, furnishes low voltagecurrent for operating the automatic tuning device. As already stated,current is supplied to the various connections 34 by the contact arms 38from the shaft 31. To this end, one terminal of the secondary of thetransformer 42 is connected to a contact finger 43 driven by the clock35 at a speed of one revolution per hour. The finger 43 engages one offour contacts 44 every quarter hour. The contacts 44 are all connectedtogether, as indicated by the conductor 45, and the group of contacts isconnected to a brush 46 engaging a slip ring 4l carried on the shaft 3land in electrical contact therewith. rihe purpose of the nger 43 and thecontacts t4 is to close the control circuit precisely at quarter hourintervals as it would be difficult to obtain accurately timed operationsby relying solely on the engagement of the arms 38 of the projections2S. A manual switch 4S is provided for connecting the iinger 43 with theconductor 45, when desired, for a purpose which will be described later.

As will be apparent from the description so far, the disks 25 (exceptthe on and off disks 25a and 25h) are associated with the various broscasting stations which are tuned in automatically by the automatictuning device on energization of the connections 34. Legends may beplaced on the sloping wall l5 of the case I0 to indicate the stationwith which each disk is identified. As already indicated, furthermore,two of the. disks, such as 25a and 25h are employed to control the onand off switch 4B.

As shown in Figure 6, the on disk 25a is adjusted so that its projection29 will be engaged by its arm 38 at six P. M as indicated by the clock35. The off disk 25b has its projection set at the twelve P. M.position. The first station disk 25C has its projection set also for 6P. M. while the second station disk 25d has its position set for nine P.M. It 'will be understood that additional disks are provided up to thecapacity of the automatic tuning device incorporated in the receiver 39,but since the construction and operation of all are similar, it isunnecessary to describe more than those illustrated in Figure 6.

Assuming that the disks have been adjusted as shown and the manualswitch 4l closed, conditions remain unchanged until the arm 38,associated with the disk 25, engages the projection 29 thereon. Thisoccurs substantially at six P. M. as indicated by the clock 35.Precisely at the hour, the `linger 43 engages one of its contacts 44. Acircuit is thus completed for the right-hand coil of the switch 4U. Itsmoving contact is thereby actuated to the dotted line position toconnect the receiver to the supply source. At the same time, the arm 38,associated with the disk 25C, engages the projection 29 on the latter.In a similar manner, this energizes the connection 34, associated withthe disk 25C, and extending to the automatic tuning device of thereceiver 39. The latter is immediately actuated to cause the tuningshaft of the receiver to turn to a position such that the stationidentified with the disk 25c is tuned in. Conventional automatic tuningdevices usually include a motor and suitable control members. Sincethese details form no part of the present invention, they are notlillustrated herein. I have, however, illustrated a return connection 49for completing the circuit from the automatic tuning device for thesecondary winding of the transformer 42. The automatic tuning deviceincludes means whereby the driving motor is deenergized at the propertime so it is immaterial that the circuit established by the engagementof the arm 38 with the projections 29 of the disk: 25C is maintained fora period of some moments after the automatic tuning has beenaccomplished.

The next operation occurs when the contact arm 38, associated with disk25d, engages the projection 29 on the latter. This causes a secondoperation of the automatic tuning device to change the tuning of thereceiver 39. When the i.

arm 38, associated with the disk 25h, engages its contact 29, a circuitis completed for the lefthand or off coil of the switch 4G. The movingcontact of the latter is thereby restored to the position illustrated insolid lines and the entire apparatus is deenergized, except for thetrans former 42.

As explained above, the invention makes it possible to preselect aprogram for an extensive period and to cause any desired station to betuned in at the proper time. If it is desired to tune in a particularstation at a time intermediate the quarter hours, it is only necessaryto shift the disk identified with that station to a. position as shownby the scale 26, corresponding to the time indicated by the clock 35.Incidentally, the face of the clock is preferably exposed in the endwall of the case l0. Closure of the switch 48 will complete a circuit tothe automatic tuning device in the manner already described, making itunnecessary to wait for the next quarter hour before effecting thedesired tuning. This is desirable where the case I0 is located at adistance from the receiver, as it may conveniently be, by a suitablecable. Otherwise, the receiver may be manually tuned to any station atany time. In case it is desired to tune in only a few of the stationswithin the range of the receiver, it is desirable to turn the knobs 33,associated with the disks identified with the stations which it is notdesired to receive. This will prevent an accidental setting of two ofthe disks 25 for the same time. With the construction described, it ispossible to cause the receiver to tune in any desired station at anyhour during the day and a program may be selected as much as twenty-fourhours in advance.

It will be apparent from the foregoing that the invention provides asimple and relatively inexpensive apparatus, whereby the automatictuning device of a conventional receiver having a rotary tuning shaftmay be caused to tune in a plurality of stations successively atpreselected times.

The operation of the invention, furthermore, is so simple that it can bemastered by an entirely unskilled person with the aid of briefinstructions.

Although I have illustrated and described herein but a preferredembodiment ofthe invention, it will be understood that changes in theconstruction and arrangement disclosed may be made without departingfrom the spirit of the invention or the scope of the appended claims.

I claim:

1. Apparatus for closing control circuits at preselected times,comprising a plurality of bushings, means supporting said bushings inaxially spaced alinement, a disk journaled on each bushing for rotaryadjustment, each of said disks having a time scale on its periphery anda contact ring on one face with a projection extending therefrom, ashaft extending through said bushings having a contact arm forengagement with the projection on each disk, and means for driving saidshaft.

2. Apparatus for closing control circuits at preselected timescomprising a plurality of disks,

one for each of said circuits, a bushing, a support for said bushing,said disks being journaled in pairs for rotation near opposite ends ofsaid bushing, and having contact members on one face, a shaft extendingthrough the bushing,

and contact arms on said shaft for cooperation d with said members.

3. In a p-reselecting apparatus, a bushing having a peripheral groove, aforked standard adapted to receive said bushing and enter said groove, aselecting disk journaled on the bushing, having a contact memberthereon, a shaft extending through said bushing, and a nger on saidshaft adapted to engage said contact.

ROBERT E. MCCLURE.

